Al Gore offered Americans a continuation of Bill Clinton's centrist policies dressed in more class-conscious language in his acceptance speech to the Democratic convention in Los Angeles, and then set off at once for the battleground states where the US election will be won and lost in November.

Mr Gore's speech was universally seen as the most important 51 minutes of his political life, because he had to calm the worries of a party that feared he was a loser and persuade the general public that he has what it takes to set his stamp on the post-Clinton era.

Early assessments were that Mr Gore did what he had to do, energising his supporters and reaching out to uncommitted voters in a more conversational style than he has achieved in the past.

Thursday's news that a new grand jury had been empanelled in Washington to examine Mr Clinton's conduct in the Monica Lewinsky affair failed to derail either Mr Gore's big moment in Los Angeles or the politically crucial American media coverage of it yesterday. None of the US television networks featured the Clinton story on breakfast time bulletins, while the Los Angeles Times relegated the story to an inside page.

The now officially nominated Democratic presidential candidate and his running mate, Joe Lieberman, lost no time in taking their message to middle America. Only hours after wrapping up the conven tion in California, they boarded a river boat in La Crosse, Wisconsin, to begin a campaign trip down the Mississippi under the banner "Setting Course for America's Future".

In what many see as the crucial line of his speech Mr Gore told the 4,000 delegates: "I stand here tonight as my own man, and I want you to know me for who I truly am." Those words marked a climactic moment in the vice-president's long and sometimes laboured struggle to define his political personality in terms with which both he and the voters can be at ease.

Mr Gore's speech reflected what may be an irreconcilable problem facing not just the Democrats but all third way political strategies. Mr Gore needs to stop the centrist voters, whom Bill Clinton successfully courted, from reverting to Mr Bush, but at the same time he needs to mobilise his own core support to turn out on November 7 and to prevent the left from defecting to the Green candidate, Ralph Nader.

Mr Gore's policy prescriptions were generally Clintonite: fiscal discipline (he promised to balance the budget every year he is in office), guaranteed health care for children, prescription drug benefits for the elderly, universal pre-school education, and a continued expansion of community policing (Mr Gore also promised to bring the crime figures down each year).

As in Mr Bush's speech to the Republican convention two weeks earlier, there was only a brief discussion of American foreign policy. Mr Gore said nothing about national missile defence.

Throughout his speech Mr Gore used a language which Mr Clinton generally avoids. He presented himself as a "fighter" - the term was used repeatedly both by and about Mr Gore all week. "I've taken on the powerful forces. And as president I'll stand up to them and I'll stand up for you," he said.

He also appeared to go some way towards tightening the US stance on global free trade policy, pledging standards on child labour, workers' rights and the environment. Free trade must "lift everyone up, not bring anyone down", Mr Gore said.

Early in his remarks, he paid tribute to Mr Clinton. "Millions of Americans will live better lives for a long time to come because of the job that's been done by President Bill Clinton," he said. But that was the one and only mention of the leader whom Mr Gore has served with for eight years. "This election is not an award for past performance," Mr Gore said.

Towards the end of his speech Mr Gore addressed some of his perceived failings head-on. "I know my imperfections. I know that sometimes people say I'm too serious, that I talk too much substance and policy. Maybe I've done that tonight."

The crowd roared back that he had done no such thing, even though Mr Gore's address was full of detailed pledges on domestic issues with middle American voters in mind - "working families" as Mr Gore repeatedly calls them.

Mr Gore went on: "If you entrust me with the presidency, I know I won't always be the most exciting politician. But I pledge to you tonight: I will work for you every day and I will never let you down."

The final reckoning

Gone but not forgotten

The 21 plane trees removed from the area before the convention because police believed they could be used as weapons by protesters. They are now due to be replaced.

Al Gore "If you entrust me with the presidency, I know I won't always be the most exciting politician but I pledge to you tonight: I will work for you every day and I will never let you down"

Slogan on T-shirt for sale near the convention

Let's lick Bush and Dick

Back to reality The convention stages were kept intact for an extra day so that they could be used for the filming of The West Wing, a series about the White House

Award for dance Tipper Gore for an impromptu boogie on stage before her husband was introduced

Number of times Gore mentioned the word "fight" in his speech 20

One of the biggest cheers of the night Gore's stated support for a woman's right to choose

Money raised for the Gore campaign at a party hosted by Barbra Streisand $5.2m